The answer is (x+3)(x+5).
Answer:
The confidence interval of standard deviation is: 
to 
Step-by-step explanation:
Given
See attachment for the formatted data
Solving (a): The mean
This is calculated as:
So, we have:
Solving (b): The standard deviation
This is calculated as:
--- approximated
Solving (c): 95% confidence interval of standard deviation
We have:
So:
Calculate the degree of freedom (df)
Determine the critical value at row and columns 
and 
So, we have:
---- at
--- at
So, the confidence interval of the standard deviation is:
to 
to 
to 
to
Answer:
-5 is more positive than -6. SO bigger, I think means less negative, so -5.
Step-by-step explanation:
The percentage of the radioactive isotope left is 25.0000%.
<h3>What is the half life?</h3>
The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.
Now;
We are told that;
Half life (t1/2) = 55 days
Time taken (t) = 115 days
Ratio of isotope remaining = N/No
Thus;
N/No = (1/2)^t/t1/2
N/No = (1/2)^115/55
N/No = (1/2)^2
N/No =1/4
Hence, the percentage = 1/4 * 100/1 = 25.0000%
Learn more about half life of an isotope:brainly.com/question/16387602
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Answer: n=451
8*42+3*59-62=n
336+177-62=n
451=n
n=451
